Classifications

• • C—CHEMISTRY; METALLURGY
  • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
  • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
  • C04B28/00—Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements
  • C04B28/14—Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements containing calcium sulfate cements
• • C—CHEMISTRY; METALLURGY
  • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
  • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
  • C04B2111/00—Mortars, concrete or artificial stone or mixtures to prepare them, characterised by specific function, property or use
  • C04B2111/00474—Uses not provided for elsewhere in C04B2111/00
  • C04B2111/00612—Uses not provided for elsewhere in C04B2111/00 as one or more layers of a layered structure
  • C04B2111/0062—Gypsum-paper board like materials
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
  • Y02W30/00—Technologies for solid waste management
  • Y02W30/50—Reuse, recycling or recovery technologies
  • Y02W30/91—Use of waste materials as fillers for mortars or concrete

Definitions

• a method for making a gypsum product comprises forming a slurry comprising gypsum, water and an emulsion comprising a nonsaponifiable wax, a saponified wax, an alkyl phenol component, a dispersant/surfactant, a carboxymethylcellulose component, and water.
• the nonsaponifiable wax may comprise about 33% to about 35% of the emulsion, by weight, the saponified wax may comprise about 3% to about 5% of the emulsion, by weight, the alkyl phenol component may comprise about 0.5% to about 2.5% of the emulsion, by weight, the dispersant may comprise about 0.5% to about 2% of the emulsion, by weight, and the carboxymethylcellulose component may comprise about 0.2%) to about 5% of the emulsion, by weight.
• the emulsions may comprise a preservative, e.g., a biocide (mildewcide, fungicide, etc.).
• gypsum products including gypsum board and composites made using gypsum, such as gypsum fiber composites, glass fiber-filled gypsum products, gypsum wood fiber products, etc. (collectively referred to as 'gypsum products'), may employ emulsions described herein to provide water resistance (hydrophobicity) to such products.
• emulsions When these emulsions are used, the maximum water absorption realized by such products is reduced as compared to products for which such emulsions are not used, i.e., the emulsions improve the water resistance characteristic of the products.
• these emulsions ameliorate the detrimental effects that absorbed water can have on such products, including causing dimensional instability (swelling), loss of mechanical strength and biological degradation.
• the emulsions may also serve as carriers for optional additives such as fire retardants and preservatives which are not themselves water-repellant.
• the manufacture of gypsum products generally comprises preparing a gypsum-containing slurry that contains gypsum and other components of the finished product, and then processing the slurry to remove the water and form and dry the remaining solids into the desired form.
• the gypsum is rendered into a slurry which must flow onto a paper substrate.
• the slurry/substrate combination is then sized in a continuous process by passing this combination between rollers. Simultaneous with this sizing step, a paper backing is positioned over the sized gypsum slurry. Accordingly, the gypsum slurry must possess sufficient fluidity so that a properly sized gypsum board can be made. Fluidity refers to the ability of the gypsum slurry to flow.
• Foamability refers to this ability to be foamed.
• Foamability is important to this ability of the gypsum slurry to back flow at the rollers nip.
• Forming plates may be used, eliminating the use of a master roll, but foam is important to control density of the finished product.
• the manufacture of gypsum board is a continuous manufacturing process wherein the gypsum slurry flows onto a substrate which then passes through sizing rollers. Therefore, the extent to which the gypsum slurry flows after it is sized is critical to maintaining the finished product dimensions of the gypsum board.
• the time interval from when the slurry is sized to when the gypsum slurry ceases its flow is referred to as the pre-set time. Therefore, pre-set time is an important property of the gypsum slurry.
• the set time of the gypsum slurry is also an important property.
• the set time refers to the amount of time it takes the gypsum slurry to be dried, under heat, to the finished, solid gypsum board. As is well known in the art, in a continuous gypsum board manufacturing process, it is important that the gypsum slurry possess a consistent set time.
• a GWF product is facilitated through a conventional paper making process.
• the process of water felting dilute aqueous dispersions of various fibrous materials is a well-known commercial process for manufacturing many types of paper and board products.
• an aqueous dispersion of fiber, binder and other ingredients, as desired or necessary is flowed onto a moving foraminous support wire, such as that of a Fourdrinier or Oliver mat forming machine, for dewatering.
• the dispersion may be first dewatered by gravity and then dewatered by vacuum suction means; the wet mat is then pressed to a specified thickness between rolls and the support wire to remove additional water.
• the pressed mat is then dried in heated convection or forced air drying ovens, and the dried material is cut to the desired dimensions.
• the manufacture of gypsum wood fiber products may be carried out similarly, utilizing a wet end section headbox distribution mechanism distributing the gypsum wood fiber slurry onto a vacuum wire for initial mat formation and dehydration followed by compression through a series of vacuum belt rolls and into a kiln for final dehydration.
• the addition of the emulsion does not cause wax plating or break-out on the vacuum belt.
• the gypsum wood fiber of the present invention does not incorporate paper face and back paper but rather is a paperless core that has similar performance and uses comparable to conventional sheathing products currently available.
• An emulsion as described herein is used in the manufacture of a gypsum product (gypsum board, gypsum wood fiber products, etc.) by incorporating the emulsion into the gypsum-containing slurry that is used to make the gypsum product.
• a gypsum product gypsum board, gypsum wood fiber products, etc.
• Such an emulsion may comprise a wax component comprising a nonsaponifiable wax and a saponified wax (which may be formed during the preparation of the emulsion by the reaction of a saponifiable wax and a saponifier), an alkyl phenol component, a dispersant/surfactant, a carboxymethylcellulose component, and water.
• these emulsions are optionally free of starch such as a complexed starch, and/or free of co- surfactants such as calcium lignosulfonate, sodium lignosulfonate and/or trisodium phosphate.
• the emulsion typically is added in an amount designed to provide about 1.5 weight % (wt. %) to about 3 wt. % wax in the finished product.
• the processing of the slurry is believed to break the emulsion, which releases the waxes therein and allows the waxes to migrate to the surface of the product, thus enhancing the water- resistance characteristics.
• Suitable nonsaponifiable waxes include paraffin waxes, slack waxes and scale waxes. Such waxes are commercially known to be of low volatility, exhibiting less than about a 10%) loss in weight during standard thermogravimetric analysis. Also, the oil content of these waxes is typically less than about 5% by weight, preferably less than about 1% by weight.
• Saponification of such waxes occurs as a result of combining the wax with a saponifier, i.e., strongly basic material such as ammonium hydroxide or an alkali metal hydroxide such as sodium hydroxide or potassium hydroxide.
• a saponifier i.e., strongly basic material such as ammonium hydroxide or an alkali metal hydroxide such as sodium hydroxide or potassium hydroxide.
• the amount of saponifier needed to saponify a wax may be calculated based on the saponification value of the wax. For example, the saponification value divided by 1000 equals the grams of potassium hydroxide to add per gram of wax.
• the wax component may be present in an amount of about 25 percent by weight (wt. %>) to about 50 wt. %>, based on the total weight of the emulsion, preferably about 30 wt. % to about 40 wt. %.
• the wax component comprises a combination of a nonsaponifiable wax having a melting point of greater than or equal to about 120°F and a saponifiable wax.
• the nonsaponifiable wax may comprise about 25 wt. % to about 44 wt. % of the total weight of the emulsion, and the saponifiable wax may comprise about 0.5 wt. % to about 5 wt.
• a strongly basic compound is added to the emulsion mixture to saponify the saponifiable wax.
• the saponifier may comprise, e.g., ammom ' um hydroxide or an alkali metal hydroxide, e.g., sodium hydroxide or potassium hydroxide.
• the alkali metal hydroxide may be provided in the form of a concentrated aqueous solution that may comprise about 45 % alkali metal hydroxide, by weight.
• Ammonium hydroxide may be provided in solid form.
• the saponifier may be provided in an amount of about 0.15% to about 4.5%, optionally about 0.5% to about 3%, of the emulsion, by weight.
• concentrated aqueous saponifier may be provided in an amount of about 0.5 to about 3% by weight of the emulsion; ammonium hydroxide may be added in solid form in an amount of about 0.15 to about 3% by weight of the emulsion.
• the amount of saponifier may be varied with the type of saponifiable wax used, or with the type of wood.
• an emulsion as described herein may have a pH of about 8.5 to about 12.5, for example, a pH of about 8.5 to about 9.5.
• Exemplary carboxymethylcellulose materials useful in these emulsions have molecular carbon chain lengths of about 20 to about 50 carbons.
• An example of a suitable carboxymethylcellulose is carboxymethylcellulose sodium, available from Perm Carbose, Somerset, Pennsylvania, under the trade designation LT-30, which is described as having carbon chain lengths of about 26 to 30 carbons.
• Other suitable carboxymethylcellulose materials include Perm Carbose LT-20 and LT-42.
• the carboxymethylcellulose and the product of its reaction with the saponifier or with any other component in the emulsion are referred to herein as the "carboxymethylcellulose component".
• a salt of polynaphthalenesulfonic acid is useful in the emulsions described herein and, without wishing to be bound by theory, is believed to act as a dispersant/surfactant.
• the salt may be the product of an in-situ reaction of polynaphthalenesulfonic acid and a saponifier, e.g., an alkali metal hydroxide.
• a saponifier e.g., an alkali metal hydroxide.
• One commercially available polynaphthalenesulfonic acid is DISAL GPS which may be obtained from Handy Chemical, Montreal, Quebec, Canada.
• the acid and acid salt are referred to collectively as a polynaphthalenesulfonic acid component or, more broadly (to include substitute materials), as the dispersant/surfactant.
• the dispersant/surfactant may comprise about 0.1% to about 5% of the emulsion, by weight, optionally about 0.25 wt. % to about 5 wt
• alkyl phenols include polymerized methylene-coupled alkyl phenol, phenate salts, calcium phenates, long branched chain calcium alkyl phenols, long straight chain calcium alkyl phenols and complex polymers of maleic acid with and without an amine group substitution.
• the long chain alkyl group may be a polymeric group such as a polyethylene, polypropylene, or polybutylene group, for example.
• the alkyl substituents may be a mixture of different chain lengths as is often the case with commercially available materials.
• the alkyl phenol is chosen so that the average carbon chain length of the alkyl portion matches, i.e., is approximately the same as or is close to, the average carbon chain length of the carboxymethylcellulose.
• an alkyl phenol of average chain length in the range of about C 2 to about C 3 may be used in an emulsion comprising carboxymethylcellulose having an average chain length of about 26 to about 32 carbons, e.g., Carbose LT-30 carboxymethylcellulose.
• the alkyl group of the alkyl phenol can be derived from a corresponding olefin; for example, a C 26 alkyl group is derived from a C 26 alkene, preferably a 1-alkene, a C 3 alkyl group is derived from a C 34 alkene, and mixed length groups are derived from the corresponding mixture of olefins.
• the alkyl group is an alkyl group having at least about 30 carbon atoms, however, it may be an aliphatic group (or a mixture of such groups) made from homo- or interpolymers (e.g., copolymers, te ⁇ olymers) of mono- and di- olefins having 2 to 10 carbon atoms, such as ethylene, propylene, butene- 1, isobutene, butadiene, isoprene, 1-hexene, and 1- octene.
• Aliphatic hydrocarbyl groups can also be derived from halogenated (e.g., chlorinated or brominated) analogs of such homo- or interpolymers.
• Such groups can, however, be derived from other sources, such as monomeric high molecular weight alkenes (e.g., 1-tetracontene) and chlorinated analogs and hydrochlorinated analogs thereof, aliphatic petroleum fractions, particularly paraffin waxes and cracked and chlorinated analogs and hydrochlorinated analogs thereof, white oils, synthetic alkenes such as those produced by the Ziegler-Natta process (e.g., poly(ethylene) greases) and other sources known to those skilled in the art.
• Unsaturation in the hydrocarbyl groups can be reduced or eliminated, if desired, by hydrogenation according to procedures known in the art. Preparation by methods and materials that are substantially free from chlorine or other halogens is sometimes preferred for environmental reasons.
• More than one alkyl group can be present, but usually no more than 2 or 3 are present for each aromatic nucleus in the aromatic group. Most typically only one hydrocarbyl group is present per aromatic moiety, particularly where the hydrocarbyl-substituted phenol is based on a single benzene ring.
• alkyl phenol and product of the reaction of an alkyl phenol with a saponifier or with any other component of the emulsion is referred to herein as the alkyl phenol component.
• the amount of alkyl phenol component present in the emulsion is about 0.25 wt. % to about 10 wt. %, optionally about 0.5 wt. % to about 2.5 wt. % based on the total weight of the emulsion.
• alkyl phenol component useful in the compositions of the present invention is commercially available under the trade designation 319H from Lubrizol Chem. Corp. Wycliffe, Ohio, which material is described as a C 24 - C 34 polymerized methylene-coupled alkyl phenol.
• alkyl phenols that may be used in these emulsions, include the following (identified by arbitrary identifier numbers in the following Table 1 :
• One method of manufacture for the emulsions described herein results in time, energy, operator, and production efficiencies.
• the method involves mixing the ingredients of the emulsion in a single vessel and then conveying the mixture of a homogenizer under conditions such as the following.
• An advantage of this method is that the emulsion mixture is prepared in a single vessel; it is not necessary to prepare and separately store partial mixtures of the ingredients of the emulsion in separate vessels before combining them together.
• the nonsaponifiable wax e.g., 3816 wax, further described below
• molten form e.g., at about 10°F above its melt point temperature
• water is provided at a temperature that will not cause the wax to solidify.
• the vessel is then charged in the following illustrative manner: a. Charge the melted nonsaponifiable wax, e.g., 3816 wax, at a temperature of about 189°F to about 192°F (about 87°C to about 89°C); b. Start heat and agitation; c.
• the emulsion composition is passed from the homogenizer to a cooler to achieve a first exotherm of, e.g., about 10°F to about 20°F degrees lower than the homogenizer exit temperature, and then to a cooling tank to achieve a second exotherm of, e.g., about an additional 5°F to about 15°F lower, optionally under agitation.
• the first exotherm may occur by cooling from about 130°F to about 110°F
• the second exotherm may occur by cooling from about 110°F to about 70°F.
• using a two- exotherm cooling process allows a phasing process of the formation of the emulsion to proceed to completion.
• the viscosity of the emulsion is more stable over time and the emulsion is more stable when subject to shear agitation than if a single exotherm cooling process is used.
• a batch process may be used in which a first premix comprising the molten waxes and alkylphenol may be prepared, and a second premix (an aqueous premix) comprising the water, carboxymethylcellulose and polynaphthalenesulfonic acid and saponifier may be prepared, and the first and second premixes may then be combined in a mixing tank for a time sufficient at least for the waxes to become saponified, e.g., for one to three hours, and the resulting mix may then be passed to a homogenizer and cooled as described above.
• An emulsion as described herein may have a viscosity of about 10 to about 100 centipoise, measured on a Brookfield viscometer.
• One sample emulsion had a viscosity of 9 cps at about 40% solids.
• the stability and shear performance and lack of foam generation further enhance the ability to receive these emulsions. For example, one sample emulsion remained intact even after four minutes agitation in a food blender. Embodiments of these emulsions have been demonstrated not to contribute to biological activity.
• a series of sample emulsions was made with the following common ingredients: 33%> nonsaponifiable wax; 3% montan wax, 0.5% alkylphenol; 2% polynaphthalenesulfonic acid (or, where noted 2.5%); 0.5% carboxymethylcellulose.
• the various emulsions were made with the quantity of saponifier, the nonsaponifiable waxes and with additional components in the amount set forth in the following Table 4, with water comprising the balance.
• the samples of Table 4 were prepared using the batch process described above.
• Test specimen slurries were made by mixing 50 grams of gypsum, 35.97 grams of water, and 1.92 grams of an emulsion set forth in Table 4. In a control slurry, no emulsion was added. Gypsum and water and, if added, emulsion, were mixed together and left to stand for one minute. This mixture was then mixed for an additional 30 seconds. After this second mixing, the specimen slurries were subjected to fluidity testing.
• any liquid in the remaining foam in the blender cup is drained and discarded.
• a clean, tared, 150 ml beaker is filled with the remaining foam to overflowing and the excess is struck off.
• a second foam density is determined as just described.
• the slurries containing emulsions of Table 4 yielded foam densities that were acceptable (i.e., compared favorably to the control) and ranged from about 40 to about 65 grams per 150 ml, for the measurements made at 20 seconds, and from about 10 to about 45 grams per 150 ml, for the measurements made at 2 minutes.
• One embodiment of a method for making a gypsum wood fiber product comprises:
• step (c) partially drying the mat of step (b);
• One or more preservatives may optionally be included in a gypsum product by incorporating the preservative into the emulsion or into the gypsum-containing slurry.
• a preservative suitable for gypsum products is a bactericide/fungicide known commercially as METASOL D3TA, which comprises 3,5-dimethyl-tetrahydro-l,3,5,2 H thiadiazine-2-thione.
• METASOL D3TA may be obtained from Ondo-Nalco, Houston, Texas.
• the chamber is further prepared for the test by placing a tray of greenhouse-grade potting soil in the chamber above the water, and inoculating the soil with cultures of Aureobasidium pullulans, Aspergillus niger and Penicillium. The mold is allowed to sporulate and equilibrate with the chamber for about two weeks. Test panels may then be hung in the chamber with the bottom about 75 millimeters above the inoculated soil. Mold growth on the surface of the panels is noted weekly for four weeks. Under such a test, if a panel supports mold growth, moderate mold growth is evident within 2 to 3 weeks. After the initial two weeks of the test period, none of the samples show signs of mold growth.
• fire retarding chemicals such as borax/boric acid, guanylurea phosphate-boric acid, dicyandiamide phosphoric acid formaldehyde, diethyl-N,N- bis(2-hydroxyethyl)- aminomethyl phosphate, and combinations comprising one or more of the foregoing additives.
• fire retardants are readily inco ⁇ orated into nanoparticles formed, for example, from polyvinylpyridine or polyvinylchloride.
• Other additives that are confer desirable characteristics and which may be added to the compositions include water repellants, colorants, UV inhibitors, adhesive catalysts, and combinations comprising one or more of the foregoing additives.

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• Chemical & Material Sciences (AREA)
• Engineering & Computer Science (AREA)
• Ceramic Engineering (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Inorganic Chemistry (AREA)
• Materials Engineering (AREA)
• Structural Engineering (AREA)
• Organic Chemistry (AREA)
• Paper (AREA)
• Compositions Of Macromolecular Compounds (AREA)
• Curing Cements, Concrete, And Artificial Stone (AREA)
• Agricultural Chemicals And Associated Chemicals (AREA)

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• 2004
  • 2004-06-03 WO PCT/US2004/017627 patent/WO2004108625A1/en active Application Filing
  • 2004-06-03 BR BRPI0411027-7B1A patent/BRPI0411027B1/pt not_active IP Right Cessation
  • 2004-06-03 CN CNB2004800014691A patent/CN100387540C/zh not_active Expired - Fee Related
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